25 research outputs found

    Critical loads of acidity to lakes in the Polish Tatra Mountains. A study of the yearly variations in the precipitation and water chemistry

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    As part of the Agreement on Environmental Cooperation between Norway and Poland critical loads of acidity and their exceedance to two lakes in the Polish Tatra Mountains have been calculated after an extensive programme on water chemistry and precipitation. The critical load of acidity is exceeded in Dlugi Staw, one of the two lakes in study. The main diffference between the comparable areas is the great importance of nitrogen deposition in the Tatra Mountains. The nitrogen leaching of Dlugi Staw is about 90% of the incoming nitrogen, i.e. almost all incoming nitrogen is leaving the lake as nitrate, while Zielony Staw is retaining about 50% of the incoming nitrogen. The nitrate leaching in the two Tatra lakes is much higher than the nitrate leaching of high mountain lakes in Norway subjected to similar sulphur and nitrogen deposition. Here, we find maximum leaching values of less than 30 % of the incoming nitrogen. We have no reasonable explanation for this at the present time. To be able to understand this differences, further studies are needed

    Critical loads of acidity to surface waters: A case study from the Polish Tatra Mountains

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    As part of the Agreement on Environmental Cooperation between Norway and Poland critical loads of acidity and their exceedance to lakes in the granitic area of the Polish Tatra Mountains have been estimated. Lake samples were collected in summer an autumn 1991. The results indicate that the general acidification status of the fresh water resources in the Tatra Mountains are similar to those found in similar geological setting and similar atmospheric deposition patterns in Europe and north America. The critical load of acidity is exceeded in several lakes in the area. The main difference between the comparable areas is the great importance of nitrogen deposition in the Tatra Mountains. Because of the serious acidification situation in the area, more intensive studies of deposition and yearly variations in water chemistry in several lakes shoud be carried out. The future activities should also include an extension to other potential sensitive areas in Poland

    Kinetics of cardiac and vascular remodeling by spontaneously hypertensive rats after discontinuation of long-term captopril treatment

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    Angiotensin-converting enzyme inhibitors reduce blood pressure and attenuate cardiac and vascular remodeling in hypertension. However, the kinetics of remodeling after discontinuation of the long-term use of these drugs are unknown. Our objective was to investigate the temporal changes occurring in blood pressure and vascular structure of spontaneously hypertensive rats (SHR). Captopril treatment was started in the pre-hypertensive state. Rats (4 weeks) were assigned to three groups: SHR-Cap (N = 51) treated with captopril (1 g/L) in drinking water from the 4th to the 14th week; SHR-C (N = 48) untreated SHR; Wistar (N = 47) control rats. Subgroups of animals were studied at 2, 4, and 8 weeks after discontinuation of captopril. Direct blood pressure was recorded in freely moving animals after femoral artery catheterism. The animals were then killed to determine left ventricular hypertrophy (LVH) and the aorta fixed at the same pressure measured in vivo. Captopril prevented hypertension (105 ± 3 vs 136 ± 5 mmHg), LVH (2.17 ± 0.05 vs 2.97 ± 0.14 mg/g body weight) and the increase in cross-sectional area to luminal area ratio of the aorta (0.21 ± 0.01 vs 0.26 ± 0.02 μm²) (SHR-Cap vs SHR-C). However, these parameters increased progressively after discontinuation of captopril (22nd week: 141 ± 2 mmHg, 2.50 ± 0.06 mg/g, 0.27 ± 0.02 μm²). Prevention of the development of hypertension in SHR by using captopril during the prehypertensive period prevents the development of cardiac and vascular remodeling. Recovery of these processes follows the kinetic of hypertension development after discontinuation of captopril

    Critical loads of acidity to lakes in the Polish Tatra Mountains. Final report

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    Major chemical compounds in precipitation and runoff have been intensively followed in two Polish, Tatra Mountain lakes (Dlugi Staw and Zielony Staw) since January 1993, to assess the degree of impact of acid precipitation. Since July 1995, even nitrogen and sulphur compounds in air have been measured, which means that most focus have been put on the year July 1995 - June 1996. Based on a dynamic, combined nitrogen and sulphur model (FAB), critical loads (CL) are exceeded for both lakes. While substantial reductionsof S and/or N are needed to reach CL at Dlugi Staw, only minor reductions are needed to obtain CL-level at Zielony Staw. Based on a nitrogen saturation index, both watersheds are in chronec stages of N-saturation. As long as the inputs of acid compounds are high, episodes particularly related to spring melt, may cause chemical conditions critical for aquatic life even at Zielony Staw with high acid neutralising capacity (ANC). This is primarily because the outlet streams might be totally dominated by melt water during such episodes, which means that organisms living in these streams have small changes to avoid episodes with extreme water quality. Because of far higher ANC at Zielony Staw, such episodes are both more uncommon and less extreme at this site compared with at Dlugi Staw. A surface water survey in the Karkonosze Mountains autumn 1995, documented strong impacts of atmospheric inputs of both S-and N-compounds in this area. Thus, CL is exceeded for all investigated sites

    The tragedy of liberal diplomacy: democratization, intervention, statebuilding (part I)

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    Since the end of the Cold War, democracy promotion, intervention and statebuilding have once again been explicit features of American foreign policy. Current assessments of this return, however, overlook both their longer term history and their roots in liberal (and not just American) ideology. The contradictions and dynamics entailed in the liberal philosophy of history have already played themselves out once before, in the modernization theories and policies of the early Cold War period. Despite their academic and political failures at the time, the same assumptions now underpin democracy promotion in the post-Cold War period and show signs of the same dynamics of failure. In this two part essay, I argue that the repetition of such counterproductive policies constitutes a recurring ‘tragedy of liberal diplomacy’ in which the shaping of US foreign policy by assumptions deeply rooted in the liberal philosophy of history plays a central part in producing the very enemies that policy is designed to confront and transform
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